Robinson, Williams & Spriggs v. State, 152 A.3d 661

In 2014 Maryland decriminalized possession of less than 10 grams of marijuana: such possession became a civil offense punishable by fines and treatment, but marijuana remained illegal and a Schedule I substance subject to seizure and forfeiture.
Three consolidated cases (Robinson, Williams, Spriggs) each involved officers detecting the odor of fresh or burnt marijuana emanating from a vehicle, followed by warrantless searches that uncovered larger quantities of drugs and related evidence.
Each petitioner moved to suppress evidence seized from the vehicle, arguing that decriminalization of small amounts removed probable cause for a warrantless search based solely on odor.
Trial courts denied suppression; the Court of Special Appeals affirmed (relying on Bowling v. State), and the Court of Appeals granted certiorari to decide the novel question.
The Court of Appeals held that odor of marijuana still supplies probable cause to search a vehicle because marijuana in any amount remains contraband and the odor can indicate contraband or evidence of other crimes.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether a warrantless vehicle search is supported by probable cause when an officer detects the odor of marijuana after Maryland decriminalized possession of <10 grams	Petitioners: odor alone cannot establish probable cause because possession of small amounts is a civil (noncriminal) offense and officers cannot obtain a warrant for civil offenses or reliably infer quantity by smell	State: decriminalization did not legalize marijuana; marijuana remains contraband and subject to seizure; odor gives probable cause to believe vehicle contains contraband or evidence of crime	Held: Odor of marijuana gives probable cause to search vehicles. Decriminalization does not equal legalization; marijuana in any amount remains contraband and can justify a Carroll-based warrantless search.

Carroll v. United States, 267 U.S. 132 (establishing the automobile exception: probable cause to believe a vehicle contains contraband permits warrantless search)
Florida v. Harris, 133 S. Ct. 1050 (probable cause is a practical, commonsense determination that contraband or evidence of a crime is present)
Wyoming v. Houghton, 526 U.S. 295 (automobile exception extends to personal effects in vehicle when there is reason to believe contraband or evidence is hidden in the car)
Bowling v. State, 227 Md. App. 460 (Md. Ct. Spec. App.) (holding K-9 alert to marijuana smell still provides probable cause after decriminalization)
Zuniga v. People, 372 P.3d 1052 (Colo. 2016) (odor of marijuana remains relevant to probable cause despite state legalization of small amounts)
Overmyer v. Commonwealth, 11 N.E.3d 1054 (Mass. 2014) (contrasting view: odor alone insufficient for probable cause where possession of small amounts is civil)